In December 2012, Kansas City Royals General Manager Dayton Moore made one of the biggest trades in recent memory, acquiring Tampa Bay Rays starting pitcher James Shields in exchange for four minor-league players.

At the time, the Royals hadn’t had a winning season since 2003, and even that one season was the team’s only winning season since 1993. This was a franchise in despair, so to speak. So why were the Royals acquiring “Big Game” James? Certainly, there were no big games in Kansas City’s future.

Giving up Wil Myers in the deal also was a head-scratching move, as Myers was considered one of the best young prospects in the game at the time. How could the Royals think they would be ready to compete without Myers as a centerpiece of their future?

Well, clearly Moore knew what he was doing: the Royals finished with 86 wins in 2013, and even though they didn’t make the postseason, the Kansas City organization was heading in the right direction. So the small-payroll team picked up Shields’ contract option for $13.5 million in 2014.

(Myers went on to win the American League Rookie of the Year award for the Rays in 2013, by the way.)

Shields Leads the Rotation in 2014

The Royals received 151 starts from a core group of five starters this year, and Shields was at the top of that rotation — without a doubt, as the other four guys are not even close to being household names, and that was especially true at the start of the season.

Jeremy Guthrie is an 11-year veteran with a 4.23 career ERA, but he’s now won 28 games for the Royals in two years next to Shields. After leading the AL in losses twice (2009 and 2011 with Baltimore), Guthrie has found his groove with Kansas City.

Nine-year journeyman Jason Vargas joined the Royals in 2014 and had his best season ever (3.71 ERA). After pitching for four other teams with limited success, Vargas also found his spot in the K.C. rotation behind Shields.

Rookie Yordano Ventura posted a 3.20 ERA this season, winning 14 games in the process. Fifth starter Danny Duffy posted a 2.53 ERA in a career-high 149 1/3 innings, in his fourth season with the Royals.

This is an eclectic mix of starters: one All-Star with big-game experience, two journeymen starters who complemented Shields and two young guys just hitting their strides without facing any demand or pressure to be the No. 1 guy too soon.

Shields has stabilized the staff, of course, with his experience and achievements. He’s the only pitcher in Tampa Bay history to win a World Series game, and as a member of that organization, he knew what it was like to play for — and be successful at — a small-market team in this big-money MLB era.

Yes, Dayton Moore knew exactly what he was doing when he acquired Shields, as the fortunes of his franchise have dramatically increased since Shields came to town.

Meanwhile…

The four minor-leaguers Kansas City sent to Tampa Bay are doing okay, as well, and they may yet lead the Rays to some more postseasons in their future.

But Myers — after posting a .293 average in 2013 — slumped through injuries this year, hitting just .222 in 87 games. His combined totals in two years with the Rays are 660 at-bats, 19 home runs, 88 RBI, 11 stolen bases and an .724 OPS.

Right now, it looks like the Royals got the best of this deal, even if one of the other players in the deal — starter Jake Odorizzi — won 11 games this year in the majors, striking out 174 batters in 168 innings.

In time, both those guys could be cornerstones for more Tampa Bay success, but there’s no doubt Moore pulled the trigger on a risky deal and has won big.

For small-market teams like Kansas City, Oakland and Tampa Bay, these are the kinds of deals they have to risk in order to have a chance against teams like the San Francisco Giants and their $150 million-plus payrolls.

We’ve seen the Royals and the Rays make the World Series with small payrolls, and everyone knows the “Moneyball” successes the A’s have had in getting to the playoffs eight times in the last 15 years, too.

Sometimes the big trades work for the little guys, and sometimes they don’t. In this case, Kansas City won the trade, and the organization will never have to defend its decisions again — not for a long time, especially if they go on to beat San Francisco in the Fall Classic with Shields leading the way.